函数值

Compatibility (Argument Type):
Dart Sass
✓
LibSass
since 3.5.0
Ruby Sass
since 3.5.0

函数也可以是值！你不能直接将函数写作值，但可以将函数的名称传递给 meta.get-function() 函数以获取它作为值。一旦你有了一个函数值，你就可以将它传递给 meta.call() 函数来调用它。这对于编写高阶函数（调用其他函数的函数）很有用。

Playground

SCSS Syntax

@use "sass:list";
@use "sass:meta";
@use "sass:string";

/// Return a copy of $list with all elements for which $condition returns `true`
/// removed.
@function remove-where($list, $condition) {
  $new-list: ();
  $separator: list.separator($list);
  @each $element in $list {
    @if not meta.call($condition, $element) {
      $new-list: list.append($new-list, $element, $separator: $separator);
    }
  }
  @return $new-list;
}

$fonts: Tahoma, Geneva, "Helvetica Neue", Helvetica, Arial, sans-serif;

.content {
  @function contains-helvetica($string) {
    @return string.index($string, "Helvetica");
  }
  font-family: remove-where($fonts, meta.get-function("contains-helvetica"));
}
Playground

Sass Syntax

@use "sass:list"
@use "sass:meta"
@use "sass:string"

/// Return a copy of $list with all elements for which $condition returns `true`
/// removed.
@function remove-where($list, $condition)
  $new-list: ()
  $separator: list.separator($list)
  @each $element in $list
    @if not meta.call($condition, $element)
      $new-list: list.append($new-list, $element, $separator: $separator)


  @return $new-list


$fonts: Tahoma, Geneva, "Helvetica Neue", Helvetica, Arial, sans-serif

.content
  @function contains-helvetica($string)
    @return string.index($string, "Helvetica")

  font-family: remove-where($fonts, meta.get-function("contains-helvetica"))

CSS Output

.content {
  font-family: Tahoma, Geneva, Arial, sans-serif;
}